US5732467A - Method of repairing directionally solidified and single crystal alloy parts - Google Patents

Method of repairing directionally solidified and single crystal alloy parts Download PDF

Info

Publication number
US5732467A
US5732467A US08748848 US74884896A US5732467A US 5732467 A US5732467 A US 5732467A US 08748848 US08748848 US 08748848 US 74884896 A US74884896 A US 74884896A US 5732467 A US5732467 A US 5732467A
Authority
US
Grant status
Grant
Patent type
Prior art keywords
surface
coating
crack
superalloy
directionally
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US08748848
Inventor
Raymond Alan White
Yuk-Chiu Lau
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
General Electric Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Grant date

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23POTHER WORKING OF METAL; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P6/00Restoring or reconditioning objects
    • B23P6/002Repairing turbine components, e.g. moving or stationary blades, rotors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K20/00Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
    • B23K20/02Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating by means of a press ; Diffusion bonding
    • B23K20/021Isostatic pressure welding
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23POTHER WORKING OF METAL; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P6/00Restoring or reconditioning objects
    • B23P6/04Repairing fractures or cracked metal parts or products, e.g. castings
    • B23P6/045Repairing fractures or cracked metal parts or products, e.g. castings of turbine components, e.g. moving or stationary blades, rotors, etc.
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C4/00Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C4/00Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
    • C23C4/18After-treatment
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/005Repairing methods or devices
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01DNON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12Blades
    • F01D5/28Selecting particular materials; Particular measures relating thereto; Measures against erosion or corrosion
    • F01D5/288Protective coatings for blades
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49316Impeller making
    • Y10T29/49318Repairing or disassembling
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49316Impeller making
    • Y10T29/49336Blade making
    • Y10T29/49339Hollow blade

Abstract

A new method is provided for repairing cracks in the outer surfaces of structural parts being a superalloy article having a directionally oriented microstructure, such as a blading member. The article may have internal passageways communicating through the end of the article. The method coats and seals cracked outer-surface areas of directionally solidified and single crystal structures by coating the defective area using a High Velocity Oxy-Fuel process (herein also referred to as HVOF), followed by hot isostatic pressing the part.

Description

FIELD OF THE INVENTION

The present invention relates to a method of repairing defects in directionally solidified and single crystal alloy parts. More particularly, the invention is directed to methods for repairing surface cracks in structural alloy parts, such as engines, by cleaning, coating, and hot isostatic pressing the part to provide a leak-free repaired area, while maintaining the crystalline structure and mechanical properties of the alloy part.

BACKGROUND OF THE INVENTION

The reported technology for growing directionally oriented cast structures from superalloys has evolved from processes suitable for making simple shapes and members to processes that are currently used to form articles having complex shapes, such as the directional solidification of nickel-base superalloy blading members used in the hot sections of gas turbine engines. The published literature, such as Metals Handbook Ninth Edition, Vol. 15 Casting, ASM international (1988), pages 319-323, has many examples of processes for making directionally oriented, superalloy blading members, such as turbine blades and vanes. Most of these processes utilize some form of a withdrawal-type vacuum induction casting furnace with mold susceptor heating.

An example of a blading member having a complex shape of the type described above is the turbo machinery blade described in U.S. Pat. No. 4,010,531. Such a blading member comprises an airfoil-shaped outer wall having a complex hollow interior communicating with an end region, such that gases can be circulated from the hollow interior through the outer wall and end region for cooling purposes, wherein the end region comprises a tip that extends from the end of the member.

Airfoil blading members, are frequently utilized in extreme environments where they are exposed to a variety of environmentally related damage and wear mechanisms, including: erosion due to impact by high velocity and high temperature airborne particles, high temperature oxidizing and corrosive gases, low-cycle fatigue processes and mechanical abrasion caused by rubbing against other members. These mechanisms are known to cause cracking and other damage, particularly in the end regions or tips of these members. Because the manufacturing costs for blading members are typically relatively high, it is often desirable to repair them rather than to replace them after the blades have been damaged or worn.

When blading members, or other articles having a directionally oriented microstructure are damaged with a crack, whether in operation or during manufacturing, the problem of repairing the surface crack becomes more complicated and difficult. This problem of repair becomes particularly acute when a directionally oriented microstructure must be maintained in the repaired portion, as is frequently desirable in directionally oriented articles such as airfoils, because of the difficulty of replicating the original directional orientation in the materials used to make the repairs.

One method that has been used for the repair of turbine blades, has been to add material to the damaged or cracked portion by welding, or similar processes. A disadvantage to this method is that the microstructure of the weld is not directionally oriented, and thus the mechanical properties of the repaired area are diminished as compared to the remainder of the directionally oriented microstructure of the article. Also, most current oxidation resistant materials are difficult to weld, and have been known to crack further during the welding process.

Thus, the advanced directional solidified and single crystal alloy engine parts present challenges when they have to be repaired. The main problem that has to be solved is how to preserve the directional solidified and single crystal microstructure in the repaired part. Conventional fusion welding processes would result in a multi-grained, equiaxed cast structure in the repair joints. High temperature brazing would change the chemical composition in the joint, usually by diffusion of boron, and would also produce a cast structure in the joint.

Activated Diffusion Healing (ADH) has been used for conventional superalloy repair. In the case of conventional multi-grained alloys, properties in the repair area are decreased due to boron contamination. The grain structure of the joint would also reduce properties if used to repair directional solidified and single crystal alloys.

A current technique being used to repair superalloy parts is a process known as Partitioned Alloy Component Healing (PACH). This involves blending powders of different compositions, at least one being low melting, such that the overall composition is close to that of the base metal. The part is heated above the melting temperature of the low melting constituent but below the base metal recrystallization temperature, and held at temperature until healed by activated diffusion. The technique reduces, but does not eliminate, boron contamination. Also, the joint is still multi-grained.

In an article entitled, "Gastight Plasma Sprayed Sealings for HIP Diffusion Bonding of Materials", published in the Thermal Spray Research and Applications, Proceedings of the Third National Thermal Spray Conference, Long Beach, Calif., pages 20-25, May 1990, it was suggested that the production of gastight metal coating by low pressure plasma spraying offers the possibility of a new technique for the joining of separate parts by the HIP diffusion bonding process. The reference paper teaches low pressure plasma deposition encapsulation which presents possible limitations on part size, spray gun-to-part surface access, productivity, and cost. This is partly due to the vacuum chamber within which the low pressure plasma deposition spray gun operates.

There is a need for a method of optimum repair of surface cracks in directionally solidified and single crystal superalloy parts. The optimum repair would be one that forces close the cracks, which are open to the outer surface of the part. The process would allow solid state diffusion to heal the cracks at a temperature below the recrystallization temperature of the alloy. There is also a need to maintain the mechanical properties as well as the structural integrity of the directionally solidified and single crystal part so that cracked outer surfaces are sealed for hollow engine parts, such as turbine vanes with multiple cooling holes.

SUMMARY OF THE INVENTION

In carrying out the present invention in preferred forms thereof, a new method is provided for repairing cracks in the outer surfaces of structural parts. The present invention describes methods for repairing cracks in a superalloy article having a directionally oriented microstructure, such as a blading member. The blading members include, for example, turbine blades, buckets, vanes, nozzles, and non-airfoil articles such as turbine shrouds and combustor shingles. The article may have internal passageways communicating through the end of the article. The repair may comprise equiaxed grains, where the directionally oriented crystal structure comprises a plurality of grains or a single crystal.

The invention may be briefly and generally described as a method for repairing cracks on the outer surface of an article, comprising the steps of: selecting an article having a directionally oriented microstructure and a superalloy composition, whereby said article has at least one crack on its outer surface, said crack having an opening to the atmosphere; cleaning said crack surface to sufficiently remove contaminants; coating the cleaned crack surface with a material compatible with a composition of said article; and hot isostatic pressing the coated crack surface at a temperature, pressure, and time sufficient to repair the surface crack. Basically, the invention coats and seals cracked outer-surface areas of directionally solidified and single crystal structures by coating the defective area using a High Velocity Oxy-Fuel process (herein also referred to as HVOF), followed by hot isostatic pressing the part. The result is to diffusion heal the cracks, thereby preserving the unique microstructure with its inherent mechanical property advantages. The technique of coating the surface cracks prior to hot isostatic pressing has general advantages over conventional canning techniques.

An object of this invention is to repair directionally solidified and single crystal surface cracked structures without property losses due to compositional contamination or microstructure changes with respect to the superalloy base material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a is a three-dimensional view, partly cut away, showing a typical overall inner and outer arrangement for at least one turbine bucket that is made from a directionally solidified superalloy and that has a crack on the outer surface.

FIG. 1b depicts a cross-sectional view of the cracked surface area shown in FIG. 1a.

FIG. 2a is a photomicrograph at 50× magnification of a healed crack by the method of this invention.

FIG. 2b shows the healed crack of FIG. 2a at 200× magnification.

FIG. 3A is a photomicrograph representing a surface crack before coating and hot isostatic pressing at 200×.

FIG. 3b is a photomicrograph of the representative crack of FIG. 3a after spray coating and hot isostatic pressing and shows the top closure of the crack at the part surface at 200×.

DESCRIPTION OF THE INVENTION

The present invention comprises methods to repair cracks and defects on the outer surface of directionally oriented, superalloy articles, through the cleaning, coating and hot isostatic pressing of the superalloy article. The method may be used to repair the crystal structure and overall microstructure of the superalloy article that is compatible with and continuous with that of the article. While potentially useful on a wide variety of articles, the method of this invention is particularly useful in repairing outer surface cracks on an article having a hollow interior and openings or passages communicating with the hollow interior, such as a turbine blade shown in FIG. 1a.

As used herein, the term "crystal structure" is intended to mean the overall crystal morphology, such as a single crystal, multiple elongated grains and other crystal forms, and their orientations. The terms "directionally oriented", "directional orientation" or similar terms refer to strong oriented crystal structures, including directionally solidified polycrystalline and single crystal structures comprising a plurality of elongated grains and single crystals. The desired crystal orientation in nickel-base superalloys frequently used for blading members is that the <001> crystallographic direction be parallel to the length of the member, and thus substantially parallel to the growth direction, in order to minimize the elastic modulus along the length of the member, which also corresponds to the growth direction. The term "High Velocity Oxy-Fuel" (HVOF) is a thermal spray technique for applying coatings that are fully dense having bond strengths greater than about 10,000 pounds per square inch (psi).

As noted herein, the method is particularly useful for repairing outer surface defects or cracks on an airfoil including an airfoil blading member such as a turbine blade or vane, which is depicted in FIG. 1a. A selected article, such as FIG. 1a, has a superalloy composition and directionally oriented crystal structure. The superalloy may have a superalloy composition of a nickel-base, iron-base, or cobalt-base superalloy, such as is well known and described, for example, in Metals Handbook Tenth Edition, Vol. 1, Properties Selection: Iron, Steel and High-Performance Alloys, ASM International (1990), pages 981-994 and 995-1006, which describes many castable superalloys, and specifically nickel-base superalloys that may be directionally solidified or formed as single crystals. For purposes of this invention, acceptable superalloys would also include high temperature alloys that are not presently in widespread commercial use, such as niobium-base and titanium-base alloys, including niobium-titanium alloys, directionally oriented nickel-base or titanium-base composite alloys and niobium-aluminum alloys.

Turning to FIG. 1a, the blade 1 is shown cut away to demonstrate the internal cooling passages 3 which are surrounded by an outer surface 5. Looking at FIG. 1b, the outer surface 5 is generally a superalloy metal 15 and may have coating overlays, such as a bond coat 11 and a thermal barrier coating 9. The bond coat 11 is any acceptable metallic or ceramic coating that serves to improve adhesion between the subsequent thermal barrier coating 9 and the underlying substrate 15. Examples of bond coats are MCrAlY, where M is nickel, iron, cobalt, or mixtures thereof; and aluminides. The thermal barrier coating 9 provides a protective coating that enables the substrate 15 to operate at higher temperatures. Thermal barrier coatings also protect the underlying parts from corrosive and oxidative environments. An example of a thermal barrier coating is chemically stabilized zirconia, such as yttria stabilized zirconia, where yttria is present in about 1 to 20 weight percent, with the preferred range being about 6-12 weight percent yttria.

During manufacturing or service life, many directionally solidified superalloy parts, such as blades 1, experience cracks 7 and defects in the outer surface 5. It is important to be able to repair the surface cracks 5 without affecting the internal cooling passages 3. It is also beneficial to be able to repair the cracks 7 in directionally solidified or single crystal parts so as to maintain the mechanical and structural properties.

FIG. 1b shows a cross-sectional view of an outer surface area 5 of a blade member having a surface defect or crack 7. The surface defects or cracks often are heavily oxidized areas. It is desirable to remove heavily oxidized contaminants from the surface defects and cracks. The cleaning and surface preparation can be accomplished by methods known in the art such as fluoride ion cleaning, ultrasonic agitated cleaning with or without the use of chemical cleaning compositions. The cleaning method chosen prepares the surface for subsequent coating while not attacking the mechanical properties or the crystal orientation of the part.

After cleaning and surface preparation, cracks with openings in the outermost surface are coated by Hyper Velocity Oxy-Fuel or other thermal spray process, such as low pressure plasma deposition, to seal the crack region. The preferred method of coating is the Hyper Velocity Oxy-Fuel process. The low pressure plasma deposition process, being chamber contained and therefore more costly and limiting, would be used only if the reduced atmosphere from the process was found to beneficial in reducing oxidation and gas volume in the cracked surface region. An evacuation tube may be incorporated into the spray process of the Hyper Velocity Oxy-Fuel, if required.

The coating material to seal the crack prior to hot isostatic pressing, is chosen to match the superalloy substrate material or it can be deliberately made to be different, so as to have enhanced beneficial surface properties, or to allow easy removal of the coating after hot isostatic pressing. The choice of coating must be compatible with the superalloy part material. Generally, in the context of this invention, compatibility means some continuity or similarity of crystal structure, metallurgical structure, or both, between the superalloy article and the repair of the defect by diffusion healing from the coated material. Compatibility also implies that neither the superalloy material or the coating material adversely affects the other. The coating thickness is sufficient to be HIPed and seal the crack. Generally, the thickness is about 0.001 to 0.010 inches thick before HiPing. A preferred thickness is about 0.010 inches

In accordance with this invention, after coating, the defective part is hot isostatic pressed at a suitable temperature, time, and pressure cycle to prevent recrystallization while effecting a diffusion bond at the crack surface. Following the hot isostatic pressing cycle, the coating may be removed if so designed.

FIGS. 2a and 2b show photomicrographs of a specimen that was coated and HIPed to seal outer surface cracks in superalloy parts. FIG. 2a shows the crack being sealed at the outer surface of the part at 50×. FIG. 2b demonstrates complete sealing (100% bonding) of the entire cracked area from the tip of the crack to the outermost surface of the superalloy part at 200×. This is the preferred sealing configuration and possible to achieve with sufficient cleaning.

It is further pointed out in this invention that a thermal treatment after the coating application can be beneficial to further reduce porosity in the coating and provide a leak tight structure. It will also be recognized by those skilled in the art of repair of superalloy parts, that after hot isostatic pressing the part member may still be in an unfinished form, and will, therefore, further require the use of material removal and surface finishing steps such as machining, polishing or other material removal to produce a finished part. The following examples further demonstrate, but do not limit the invention.

EXAMPLE 1

Spray coatings by HVOF of Rene 80 and pure nickel of about 0.010 inches thick were deposited on stainless steel and Rene N5 single crystal material. The substrate materials were welded together to simulate and form a crack to the exterior outermost surface. After the coating application, the coatings were found to be leak tight. The Rene N5 single crystal specimens that were coated by HVOF with pure nickel, were then hot isostatic pressed. The conditions for hot isostatic pressing were 1150° C. at 30 ksi for 3 hours. Metallography revealed that the crack was bonded 100% (FIGS. 2a and 2b).

EXAMPLE 2

Cracked single crystal Rene N4 vane segments were successfully spray coated and hot isostatic pressed for repair. FIG. 3a shows a cracked Stage I CFM56-5A HPT nozzle segment. The cracked area was cleaned using fluoride ion cleaning. The cracked surface of the vanes were sectioned from the remainder of the part and the segment end walls. The cracked surface was Hyper Velocity Oxy-Fuel sprayed with a 0.012 inch thick coating of nickel chromium alumminum yttria (NiCrAlY). The spray coating segment was then vacuum heat treated at 1150° C. for about 2 hours and hot isostatic pressed at 1150° C., 30 ksi, for about 4 hours. The vacuum heat treatment served to densify the coating and increase its ductility. Leak test specimens revealed very small through-coating leaks in the HVOF coating which sealed during vacuum heat treat densification. It can be of further benefit in the fine through-coating porosity to seal the coating during vacuum heat treatment, which would then further improve the hot isostatic pressing bonding of the crack. The sealed crack at the outer surface is depicted in FIG. 3b. It is preferred that the entire crack seal. Generally, when only a outermost portion of the crack seals, it is attributed to insufficient cleaning or removal of contaminants from the crack. Table I gives the parameters used for HVOF spraying, the heat treatment, and HIPing the cracked specimen.

              TABLE I______________________________________HIGH VELOCITY OXY-FUEL COATING    Seg. 1A      Seg. 1B______________________________________Spray Process:      HVOF           HVOFPowder:    NiCrAlY (-325/+400)                     NiCrAly (-325/+400)Powder Feed:      2.4 rpm        1.2 rpmGun Stand-off:      10"            10"Gun Speed: 1200"/min.     1200"/min.Oxygen Flow:      480 scfh       520 scfhPropylene Flow:      160 scfh       120 scfhCarrier Flow:      55 scfh (N.sup.2)                     55 scfh (N.sup.2)Thickness: .010"          .012"Post-Spray HT:      1150 C./2 hr/vac                     1150 C./2 hr/vacHIP Parameters:      1150 C./4 hr/30 ksi                     1150 C./4 hr/30 ksi      Temperature First                     Temperature First______________________________________
EXAMPLE 3

Air plasma spray trials were conducted on a Rene N5 disk that was sliced and then welded back together to create a crack specimen. A quarter inch diameter stainless steel tube was welded in the middle of one face of the disk for leak testing. The crack specimen was grit blasted and then ultrasonically cleaned in acetone. A nominal 0.010 inch thick layer of nickel chromium aluminum yttria was air plasma sprayed over the cracked face of the specimen. The spray parameters shown in Table II were used.

              TABLE II______________________________________AIR PLASMA SPRAY COATING______________________________________Powder:  NiCrAlY (-140/+325)                  Feed Rate: ≧3 lbs./hr.Gun Type:    Metco 7MB     Voltage:   75 voltsAnode:   G             Amperage:  600 ampsCathode: 7M63          Primary Gas:                             N.sup.2 @ 34 psi*Substrate:    40 rpm        Carrier Gas:                             N.sup.2 @ 32 psi*SpeedGun:     2"            Aux. Gas:  H.sup.2 @ 50 psi*Stand-OffGun Speed:    7 in./min.______________________________________ *flow rate determined by critical orifice on Miller control unit.

After spray coating, the crack volume was pressurized to 10 psi by connecting the quarter inch tube to a regulated cylinder of nitrogen. A soap solution applied to the outer surface of the spray coating indicated, by vigorous bubbling in the area of the crack that the coating was porous through its thickness. The coat specimen was then vacuum heat treated at 1150° C. for two hours in an attempt to densify the coating to effect a leak tight seal over the crack. Again, leak testing indicate large amount of through-thickness porosity. The coating was then hot isostatic pressed at 1150° C., 30 ksi, for about 4 hours. It was again leak tested after hot isostatic pressing and the cracked area still showed signs of leaking.

Another crack specimen was made as stated above, only this time a 0.020 inch thick nickel chromium aluminum yttrium (NiCrAlY) coating was applied by the air plasma spray process. The coated specimen was leak tested as-sprayed, and after vacuum heat treating for two hours at 1150° C. It leaked in both cases. It was concluded that air plasma spray may not be a suitable process for coating the cracked surfaces.

While the methods disclosed herein constitute preferred methods of the invention, it is to be understood that the invention is not limited to these precise methods, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

Claims (12)

What is claimed is:
1. A method for repairing cracks on the outermost surface of an article, comprising the steps of:
selecting an article having a directionally oriented microstructure and a superalloy composition, whereby said article has at least one crack on its outermost surface, said crack having an opening to the atmosphere;
cleaning said crack surface to sufficiently remove contaminants;
coating the cleaned crack surface with a material compatible with a composition of said article; and
hot isostatic pressing the coated crack surface at a temperature, pressure, and time sufficient to repair the crack surface while maintaining the crystalline structure and mechanical properties of the article.
2. A method according to claim 1 where the article is a blading member.
3. A method according to claim 2 where the blading member is a turbine blade, bucket, vane, nozzle, turbine shroud, or combustor shingle.
4. A method according to claim 1 where the superalloy is selected from the group consisting of nickel-base alloys, iron-base alloys, cobalt-base alloys, niobium-base alloys, titanium-base alloys, and mixtures thereof.
5. A method according to claim 4 where the directionally oriented microstructure of the superalloy is directionally solidified polycrystalline or single crystal.
6. A method according to claim 5 where the crystals of the superalloy have a crystallographic direction parallel to a length of the article comprising a plurality of elongated grains and single crystals.
7. A method according to claim 1 where the article has a bond coat and a thermal barrier coating on the outermost surface.
8. A method according to claim 1 where the coating is applied by Hyper Velocity Oxy-Fuel spray process.
9. A method according to claim 1 where the coating material is MCrAlY, where M is iron, nickel, cobalt, or mixtures thereof.
10. A method according to claim 1 where the coating thickness is about 0.001 to 0.010 inches.
11. A method according to claim 1 where after the coating step, the article is vacuum heat treated for a period of time to seal or densify the coating.
12. A method according to claim 11 where the vacuum heat treatment is between about 1000° C. to 1200° C. for about 30 minutes to about 150 minutes.
US08748848 1996-11-14 1996-11-14 Method of repairing directionally solidified and single crystal alloy parts Expired - Fee Related US5732467A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US08748848 US5732467A (en) 1996-11-14 1996-11-14 Method of repairing directionally solidified and single crystal alloy parts

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US08748848 US5732467A (en) 1996-11-14 1996-11-14 Method of repairing directionally solidified and single crystal alloy parts

Publications (1)

Publication Number Publication Date
US5732467A true US5732467A (en) 1998-03-31

Family

ID=25011185

Family Applications (1)

Application Number Title Priority Date Filing Date
US08748848 Expired - Fee Related US5732467A (en) 1996-11-14 1996-11-14 Method of repairing directionally solidified and single crystal alloy parts

Country Status (1)

Country Link
US (1) US5732467A (en)

Cited By (61)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998028458A1 (en) * 1996-12-23 1998-07-02 Arnold James E Method of treating metal components
WO1999023272A1 (en) * 1997-11-03 1999-05-14 Siemens Aktiengesellschaft Method for producing a protective coating on a base body intended to be impinged upon by a hot gas and corresponding product
WO2000017490A2 (en) * 1998-09-03 2000-03-30 Arnold James E Methods for repairing and reclassifying airfoil parts
US6050477A (en) * 1997-04-08 2000-04-18 Asea Brown Boveri Ag Method of brazing directionally solidified or monocrystalline components
US6199746B1 (en) * 1999-08-02 2001-03-13 General Electric Company Method for preparing superalloy castings using a metallurgically bonded tapered plug
US6210635B1 (en) 1998-11-24 2001-04-03 General Electric Company Repair material
US6284390B1 (en) * 1998-06-12 2001-09-04 United Technologies Corporation Thermal barrier coating system utilizing localized bond coat and article having the same
US6393828B1 (en) * 1997-07-21 2002-05-28 General Electric Company Protective coatings for turbine combustion components
EP1238742A1 (en) * 2001-02-22 2002-09-11 Hickham Industries, Inc., (Texas Corporation) Method of applying braze materials to a substrate requiring repair
US6491207B1 (en) * 1999-12-10 2002-12-10 General Electric Company Weld repair of directionally solidified articles
EP1275753A1 (en) * 2001-07-12 2003-01-15 Snecma Moteurs Process for the global repairing of a piece coated with a thermal barrier
US20030088980A1 (en) * 1993-11-01 2003-05-15 Arnold James E. Method for correcting defects in a workpiece
US6616410B2 (en) 2001-11-01 2003-09-09 General Electric Company Oxidation resistant and/or abrasion resistant squealer tip and method for casting same
US6629368B2 (en) 2001-05-14 2003-10-07 Alstom (Switzerland) Ltd. Method for isothermal brazing of single crystal components
US20040018299A1 (en) * 1996-12-23 2004-01-29 Arnold James E. Method of forming a diffusion coating on the surface of a workpiece
US20040031140A1 (en) * 1996-12-23 2004-02-19 Arnold James E. Methods for salvaging a cast article
EP1416269A1 (en) * 2002-10-31 2004-05-06 ALSTOM Technology Ltd A non-destructive method of detecting defects in braze-repaired cracks
US20040139805A1 (en) * 2002-10-31 2004-07-22 Alstom (Switzerland) Ltd Non-destructive method of detecting defects in braze-repaired cracks
US20040164059A1 (en) * 2002-11-29 2004-08-26 Alstom Technology Ltd Method for fabricating, modifying or repairing of single crystal or directionally solidified articles
US20040172825A1 (en) * 2003-03-03 2004-09-09 Memmen Robert L. Turbine element repair
US20040172826A1 (en) * 2003-03-03 2004-09-09 Memmen Robert L. Turbine element repair
US20040245323A1 (en) * 2003-06-05 2004-12-09 Offer Henry P. Fusion-welding of defective components to preclude expulsion of contaminants through the weld
US20050036892A1 (en) * 2003-08-15 2005-02-17 Richard Bajan Method for applying metallurgical coatings to gas turbine components
US20050061228A1 (en) * 2003-02-17 2005-03-24 Alstom Technology Ltd. Process for strengthen grain boundaries of an article made from a Ni based superalloy
US20050098243A1 (en) * 2003-11-06 2005-05-12 General Electric Company Method for HVOF or LPPS restoration coating repair of a nickel-base superalloy article
US6905728B1 (en) 2004-03-22 2005-06-14 Honeywell International, Inc. Cold gas-dynamic spray repair on gas turbine engine components
US20050126664A1 (en) * 2000-01-20 2005-06-16 Electric Power Research Institute, Inc. Method and apparatus for repairing superalloy components
US20050128936A1 (en) * 2003-09-15 2005-06-16 Lei Shao Apparatus and associated methods to implement a high throughput wireless communication system
US20050205415A1 (en) * 2004-03-19 2005-09-22 Belousov Igor V Multi-component deposition
US20050220995A1 (en) * 2004-04-06 2005-10-06 Yiping Hu Cold gas-dynamic spraying of wear resistant alloys on turbine blades
EP1629930A1 (en) * 2004-08-26 2006-03-01 United Technologies Corporation Method of repairing cracks in a turbine component using cathodic arc and/or low pressure plasma spraying and high isostatic pressure (HIP)
EP1629929A1 (en) * 2004-08-26 2006-03-01 United Technologies Corporation Method of repairing worn portions of a turbine component restoration using cathodic arc or Low Pressure Plasma Spraying (LPPS) and High Isostatic Pressing (HIP)
US20060045785A1 (en) * 2004-08-30 2006-03-02 Yiping Hu Method for repairing titanium alloy components
US20060086776A1 (en) * 2004-10-22 2006-04-27 Gandy David W Method to join or repair superalloy hot section turbine components using hot isostatic processing
EP1672175A1 (en) * 2004-12-14 2006-06-21 Honeywell International Inc. A method for applying environmental-resistant mcraly coatings on gas turbine components
US20060225641A1 (en) * 2003-01-10 2006-10-12 Georg Bostanjoglo Method for the production of monocrystalline structures and component
US20060248719A1 (en) * 2005-05-06 2006-11-09 United Technologies Corporation Superalloy repair methods and inserts
US20060248718A1 (en) * 2005-05-06 2006-11-09 United Technologies Corporation Superalloy repair methods and inserts
US20070039175A1 (en) * 2005-07-19 2007-02-22 General Electric Company Methods for repairing turbine engine components
US20070044306A1 (en) * 2005-08-29 2007-03-01 United Technologies Corporation Superalloy repair methods
US20080017694A1 (en) * 2003-09-24 2008-01-24 Alexander Schnell Braze Alloy And The Use Of Said Braze Alloy
US7371988B2 (en) 2004-10-22 2008-05-13 Electric Power Research Institute, Inc. Methods for extending the life of alloy steel welded joints by elimination and reduction of the HAZ
US20080166585A1 (en) * 2007-01-04 2008-07-10 Siemens Power Generation, Inc. Sprayed weld strip for improved weldability
US7404986B2 (en) 2004-05-07 2008-07-29 United Technologies Corporation Multi-component deposition
US20080210347A1 (en) * 2007-03-01 2008-09-04 Siemens Power Generation, Inc. Superalloy Component Welding at Ambient Temperature
US20080256974A1 (en) * 2005-03-18 2008-10-23 Carrier Commercial Refrigeration, Inc. Condensate Heat Transfer for Transcritical Carbon Dioxide Refrigeration System
US20090113706A1 (en) * 2007-11-06 2009-05-07 General Electric Company Craze crack repair of combustor liners
US20090229101A1 (en) * 2006-05-18 2009-09-17 Siemens Aktiengesellschaft Method of Repairing a Component, and a Component
US20090297701A1 (en) * 2005-10-07 2009-12-03 Siemens Aktiengesellschaft Process for Repairing a Component with a Directional Microstructure
US20090320966A1 (en) * 2006-08-01 2009-12-31 Siemens Power Generation, Inc. Weld repair of superalloy materials
US20090320287A1 (en) * 2005-12-15 2009-12-31 United Technologies Corporation Compressor blade flow form technique for repair
EP1013787B2 (en) 1998-12-22 2010-03-10 General Electric Company Coating of a discrete selective surface of an article
US20100242580A1 (en) * 2009-03-30 2010-09-30 General Electric Company Method for testing high temperature mechanical durability of articles
US20100291405A1 (en) * 2006-06-08 2010-11-18 Andreas Vossberg Method of producing or repairing turbine or engine components, and a component, namely a turbine or engine component
US8122600B2 (en) 2003-03-03 2012-02-28 United Technologies Corporation Fan and compressor blade dovetail restoration process
CN102712066A (en) * 2009-12-14 2012-10-03 斯奈克玛 Method for repairing a titanium blade by laser recharging and moderate hip pressing
US20130042474A1 (en) * 2011-08-17 2013-02-21 General Electric Company Rotor seal wire groove repair
CN104110276A (en) * 2013-04-17 2014-10-22 通用电气公司 A repair process and a repaired component
US20160069185A1 (en) * 2013-03-19 2016-03-10 Alstom Technology Ltd Method for reconditioning a hot gas path part of a gas turbine
CN106216937A (en) * 2016-08-16 2016-12-14 贵州安吉航空精密铸造有限责任公司 Repairing method for inside metallurgical defects of ZL114A aluminum alloy casting
CN106216936A (en) * 2016-08-16 2016-12-14 贵州安吉航空精密铸造有限责任公司 Repair method of magnesium alloy casting

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5009359A (en) * 1989-05-13 1991-04-23 Forschungszentrum Julich Gmbh Process for joining workpieces of metal or ceramic by boundary surface diffusion
US5071054A (en) * 1990-12-18 1991-12-10 General Electric Company Fabrication of cast articles from high melting temperature superalloy compositions
US5280849A (en) * 1992-10-06 1994-01-25 Commonwealth Edison Welding method for rotating shafts
US5291937A (en) * 1992-07-30 1994-03-08 General Electric Company Method for providing an extension on an end of an article having internal passageways
US5318217A (en) * 1989-12-19 1994-06-07 Howmet Corporation Method of enhancing bond joint structural integrity of spray cast article

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5009359A (en) * 1989-05-13 1991-04-23 Forschungszentrum Julich Gmbh Process for joining workpieces of metal or ceramic by boundary surface diffusion
US5318217A (en) * 1989-12-19 1994-06-07 Howmet Corporation Method of enhancing bond joint structural integrity of spray cast article
US5071054A (en) * 1990-12-18 1991-12-10 General Electric Company Fabrication of cast articles from high melting temperature superalloy compositions
US5291937A (en) * 1992-07-30 1994-03-08 General Electric Company Method for providing an extension on an end of an article having internal passageways
US5280849A (en) * 1992-10-06 1994-01-25 Commonwealth Edison Welding method for rotating shafts

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Gastight Plasma Sprayed Sealings for Hip Diffusion Bonding of Materials" by D. Stover, H.P. Buchkremer, R. Hecker and W. Mallener, Thermal Spray Research and Applications, Proceedings of the Third National Thermal Spray Conf, Long Beach CA, 25 May 1990, pp. 239-243 & Title Page.
Gastight Plasma Sprayed Sealings for Hip Diffusion Bonding of Materials by D. Stover, H.P. Buchkremer, R. Hecker and W. Mallener, Thermal Spray Research and Applications, Proceedings of the Third National Thermal Spray Conf, Long Beach CA, 25 May 1990, pp. 239 243 & Title Page. *

Cited By (111)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030088980A1 (en) * 1993-11-01 2003-05-15 Arnold James E. Method for correcting defects in a workpiece
US6049978A (en) * 1996-12-23 2000-04-18 Recast Airfoil Group Methods for repairing and reclassifying gas turbine engine airfoil parts
WO1998028458A1 (en) * 1996-12-23 1998-07-02 Arnold James E Method of treating metal components
US5956845A (en) * 1996-12-23 1999-09-28 Recast Airfoil Group Method of repairing a turbine engine airfoil part
US20040018299A1 (en) * 1996-12-23 2004-01-29 Arnold James E. Method of forming a diffusion coating on the surface of a workpiece
US20040031140A1 (en) * 1996-12-23 2004-02-19 Arnold James E. Methods for salvaging a cast article
US6050477A (en) * 1997-04-08 2000-04-18 Asea Brown Boveri Ag Method of brazing directionally solidified or monocrystalline components
US6393828B1 (en) * 1997-07-21 2002-05-28 General Electric Company Protective coatings for turbine combustion components
WO1999023272A1 (en) * 1997-11-03 1999-05-14 Siemens Aktiengesellschaft Method for producing a protective coating on a base body intended to be impinged upon by a hot gas and corresponding product
US6284390B1 (en) * 1998-06-12 2001-09-04 United Technologies Corporation Thermal barrier coating system utilizing localized bond coat and article having the same
WO2000017490A3 (en) * 1998-09-03 2000-07-13 James E Arnold Methods for repairing and reclassifying airfoil parts
WO2000017490A2 (en) * 1998-09-03 2000-03-30 Arnold James E Methods for repairing and reclassifying airfoil parts
US6387193B1 (en) 1998-11-24 2002-05-14 General Electric Company Repair material, process of repairing using the repair material, and article repaired
US6210635B1 (en) 1998-11-24 2001-04-03 General Electric Company Repair material
EP1013787B2 (en) 1998-12-22 2010-03-10 General Electric Company Coating of a discrete selective surface of an article
US6413650B1 (en) * 1999-08-02 2002-07-02 General Electric Company Method for repairing superalloy castings using a metallurgically bonded tapered plug
US6199746B1 (en) * 1999-08-02 2001-03-13 General Electric Company Method for preparing superalloy castings using a metallurgically bonded tapered plug
US6659332B2 (en) * 1999-12-10 2003-12-09 General Electric Co. Directionally solidified article with weld repair
US6491207B1 (en) * 1999-12-10 2002-12-10 General Electric Company Weld repair of directionally solidified articles
US20060138093A1 (en) * 2000-01-20 2006-06-29 Peterson Artie G Jr Method and apparatus for repairing superalloy components
US20050126664A1 (en) * 2000-01-20 2005-06-16 Electric Power Research Institute, Inc. Method and apparatus for repairing superalloy components
EP1238742A1 (en) * 2001-02-22 2002-09-11 Hickham Industries, Inc., (Texas Corporation) Method of applying braze materials to a substrate requiring repair
US20030165385A1 (en) * 2001-02-22 2003-09-04 Esch Hans Van Repair deposit of braze materials on a substrate
US6575349B2 (en) 2001-02-22 2003-06-10 Hickham Industries, Inc. Method of applying braze materials to a substrate
US6629368B2 (en) 2001-05-14 2003-10-07 Alstom (Switzerland) Ltd. Method for isothermal brazing of single crystal components
FR2827308A1 (en) * 2001-07-12 2003-01-17 Snecma Moteurs Method for comprehensive repair a part coated with a thermal barrier
EP1275753A1 (en) * 2001-07-12 2003-01-15 Snecma Moteurs Process for the global repairing of a piece coated with a thermal barrier
US20040247789A1 (en) * 2001-07-12 2004-12-09 Boucard Bruno Gilles Francois Method of globally repairing a part covered with a thermal barrier
WO2003006712A1 (en) * 2001-07-12 2003-01-23 Snecma Moteurs Method of globally repairing a part covered with a thermal barrier
US6616410B2 (en) 2001-11-01 2003-09-09 General Electric Company Oxidation resistant and/or abrasion resistant squealer tip and method for casting same
US7010987B2 (en) 2002-10-31 2006-03-14 Alstom (Switzerland) Ltd Non-destructive method of detecting defects in braze-repaired cracks
US20040139805A1 (en) * 2002-10-31 2004-07-22 Alstom (Switzerland) Ltd Non-destructive method of detecting defects in braze-repaired cracks
EP1416269A1 (en) * 2002-10-31 2004-05-06 ALSTOM Technology Ltd A non-destructive method of detecting defects in braze-repaired cracks
US20040164059A1 (en) * 2002-11-29 2004-08-26 Alstom Technology Ltd Method for fabricating, modifying or repairing of single crystal or directionally solidified articles
US6998568B2 (en) 2002-11-29 2006-02-14 Alstom Technology Ltd Method for fabricating, modifying or repairing of single crystal or directionally solidified articles
US20060225641A1 (en) * 2003-01-10 2006-10-12 Georg Bostanjoglo Method for the production of monocrystalline structures and component
US20050061228A1 (en) * 2003-02-17 2005-03-24 Alstom Technology Ltd. Process for strengthen grain boundaries of an article made from a Ni based superalloy
US7063740B2 (en) 2003-02-17 2006-06-20 Alstom Technology Ltd Process for strengthen grain boundaries of an article made from a Ni based superalloy
US8122600B2 (en) 2003-03-03 2012-02-28 United Technologies Corporation Fan and compressor blade dovetail restoration process
US7216428B2 (en) 2003-03-03 2007-05-15 United Technologies Corporation Method for turbine element repairing
US7509734B2 (en) 2003-03-03 2009-03-31 United Technologies Corporation Repairing turbine element
US20100196684A1 (en) * 2003-03-03 2010-08-05 United Technologies Corporation Turbine Element Repair
US20040172826A1 (en) * 2003-03-03 2004-09-09 Memmen Robert L. Turbine element repair
US20080057254A1 (en) * 2003-03-03 2008-03-06 United Technologies Corporation Turbine element repair
US20040172825A1 (en) * 2003-03-03 2004-09-09 Memmen Robert L. Turbine element repair
US20040245323A1 (en) * 2003-06-05 2004-12-09 Offer Henry P. Fusion-welding of defective components to preclude expulsion of contaminants through the weld
US6889889B2 (en) * 2003-06-05 2005-05-10 General Electric Company Fusion-welding of defective components to preclude expulsion of contaminants through the weld
US20050036892A1 (en) * 2003-08-15 2005-02-17 Richard Bajan Method for applying metallurgical coatings to gas turbine components
US20050128936A1 (en) * 2003-09-15 2005-06-16 Lei Shao Apparatus and associated methods to implement a high throughput wireless communication system
US20080017694A1 (en) * 2003-09-24 2008-01-24 Alexander Schnell Braze Alloy And The Use Of Said Braze Alloy
US20050098243A1 (en) * 2003-11-06 2005-05-12 General Electric Company Method for HVOF or LPPS restoration coating repair of a nickel-base superalloy article
US7811396B2 (en) 2003-11-06 2010-10-12 General Electric Company Method for HVOF or LPPS restoration coating repair of a nickel-base superalloy article
US20100136247A1 (en) * 2003-11-06 2010-06-03 General Electric Company Method for hvof or lpps restoration coating repair of a nickel-base superalloy article
US8864956B2 (en) 2004-03-19 2014-10-21 United Technologies Corporation Multi-component deposition
US20100155224A1 (en) * 2004-03-19 2010-06-24 United Technologies Corporation Multi-Component Deposition
US20050205415A1 (en) * 2004-03-19 2005-09-22 Belousov Igor V Multi-component deposition
WO2005093128A1 (en) 2004-03-22 2005-10-06 Honeywell International, Inc. Cold gas-dynamic spray repair on gas turbine engine components
US6905728B1 (en) 2004-03-22 2005-06-14 Honeywell International, Inc. Cold gas-dynamic spray repair on gas turbine engine components
US20050220995A1 (en) * 2004-04-06 2005-10-06 Yiping Hu Cold gas-dynamic spraying of wear resistant alloys on turbine blades
EP2236640A2 (en) 2004-05-07 2010-10-06 United Technologies Corporation Multi-component coating deposition
US7404986B2 (en) 2004-05-07 2008-07-29 United Technologies Corporation Multi-component deposition
US20060042082A1 (en) * 2004-08-26 2006-03-02 Michael Minor Turbine component restoration using cathodic ARC/LPPS
US7259350B2 (en) * 2004-08-26 2007-08-21 United Technologies Corporation Turbine component crack repair using cathodic arc and/or low pressure plasma spraying and HIP
US20060049236A1 (en) * 2004-08-26 2006-03-09 Michael Minor Turbine component crack repair using cathodic arc and/or low pressure plasma spraying and hip
EP1629929A1 (en) * 2004-08-26 2006-03-01 United Technologies Corporation Method of repairing worn portions of a turbine component restoration using cathodic arc or Low Pressure Plasma Spraying (LPPS) and High Isostatic Pressing (HIP)
EP1629930A1 (en) * 2004-08-26 2006-03-01 United Technologies Corporation Method of repairing cracks in a turbine component using cathodic arc and/or low pressure plasma spraying and high isostatic pressure (HIP)
US20060045785A1 (en) * 2004-08-30 2006-03-02 Yiping Hu Method for repairing titanium alloy components
WO2007027177A1 (en) * 2004-08-30 2007-03-08 Honeywell International Inc. Method for repairing titanium alloy components
US7484651B2 (en) * 2004-10-22 2009-02-03 Electric Power Research Institute, Inc. Method to join or repair superalloy hot section turbine components using hot isostatic processing
US7371988B2 (en) 2004-10-22 2008-05-13 Electric Power Research Institute, Inc. Methods for extending the life of alloy steel welded joints by elimination and reduction of the HAZ
US20060086776A1 (en) * 2004-10-22 2006-04-27 Gandy David W Method to join or repair superalloy hot section turbine components using hot isostatic processing
EP1672175A1 (en) * 2004-12-14 2006-06-21 Honeywell International Inc. A method for applying environmental-resistant mcraly coatings on gas turbine components
US20080038575A1 (en) * 2004-12-14 2008-02-14 Honeywell International, Inc. Method for applying environmental-resistant mcraly coatings on gas turbine components
US7378132B2 (en) 2004-12-14 2008-05-27 Honeywell International, Inc. Method for applying environmental-resistant MCrAlY coatings on gas turbine components
US20080256974A1 (en) * 2005-03-18 2008-10-23 Carrier Commercial Refrigeration, Inc. Condensate Heat Transfer for Transcritical Carbon Dioxide Refrigeration System
US20060248718A1 (en) * 2005-05-06 2006-11-09 United Technologies Corporation Superalloy repair methods and inserts
US7966707B2 (en) 2005-05-06 2011-06-28 United Technologies Corporation Method for repairing superalloy components using inserts
US20060248719A1 (en) * 2005-05-06 2006-11-09 United Technologies Corporation Superalloy repair methods and inserts
US20070039175A1 (en) * 2005-07-19 2007-02-22 General Electric Company Methods for repairing turbine engine components
US20070044306A1 (en) * 2005-08-29 2007-03-01 United Technologies Corporation Superalloy repair methods
EP1759799A2 (en) 2005-08-29 2007-03-07 United Technologies Corporation Superalloy repair methods
US20090297701A1 (en) * 2005-10-07 2009-12-03 Siemens Aktiengesellschaft Process for Repairing a Component with a Directional Microstructure
US8127442B2 (en) * 2005-12-15 2012-03-06 United Technologies Corporation Compressor blade flow form technique for repair
US20090320287A1 (en) * 2005-12-15 2009-12-31 United Technologies Corporation Compressor blade flow form technique for repair
US20090229101A1 (en) * 2006-05-18 2009-09-17 Siemens Aktiengesellschaft Method of Repairing a Component, and a Component
US20100291405A1 (en) * 2006-06-08 2010-11-18 Andreas Vossberg Method of producing or repairing turbine or engine components, and a component, namely a turbine or engine component
US8555500B2 (en) 2006-06-08 2013-10-15 Mtu Aero Engines Gmbh Method of producing or repairing turbine or engine components, and a component, namely a turbine or engine component
US20090320966A1 (en) * 2006-08-01 2009-12-31 Siemens Power Generation, Inc. Weld repair of superalloy materials
US7653995B2 (en) 2006-08-01 2010-02-02 Siemens Energy, Inc. Weld repair of superalloy materials
US20080166585A1 (en) * 2007-01-04 2008-07-10 Siemens Power Generation, Inc. Sprayed weld strip for improved weldability
US8618440B2 (en) 2007-01-04 2013-12-31 Siemens Energy, Inc. Sprayed weld strip for improved weldability
US20080210347A1 (en) * 2007-03-01 2008-09-04 Siemens Power Generation, Inc. Superalloy Component Welding at Ambient Temperature
US8561298B2 (en) 2007-03-01 2013-10-22 Siemens Energy, Inc. Superalloy component welding at ambient temperature
US20090113706A1 (en) * 2007-11-06 2009-05-07 General Electric Company Craze crack repair of combustor liners
US8113037B2 (en) 2009-03-30 2012-02-14 General Electric Company Method for testing high temperature mechanical durability of articles
US20100242580A1 (en) * 2009-03-30 2010-09-30 General Electric Company Method for testing high temperature mechanical durability of articles
JP2013513491A (en) * 2009-12-14 2013-04-22 スネクマ Method of repairing a titanium blade by laser filling and moderate hip compression molding
US20120276304A1 (en) * 2009-12-14 2012-11-01 Snecma Method for repairing a titanium blade by laser recharging and moderate hip pressing
CN102712066A (en) * 2009-12-14 2012-10-03 斯奈克玛 Method for repairing a titanium blade by laser recharging and moderate hip pressing
CN102712066B (en) * 2009-12-14 2016-03-23 斯奈克玛 The method of refilling and moderately hot isostatic titanium blade repair by laser
CN103732862A (en) * 2011-08-17 2014-04-16 通用电气公司 Rotor seal wire groove repair
US8893381B2 (en) * 2011-08-17 2014-11-25 General Electric Company Rotor seal wire groove repair
JP2014529704A (en) * 2011-08-17 2014-11-13 ゼネラル・エレクトリック・カンパニイ Grooves repair of rotor sealing wire
US20130042474A1 (en) * 2011-08-17 2013-02-21 General Electric Company Rotor seal wire groove repair
US20160069185A1 (en) * 2013-03-19 2016-03-10 Alstom Technology Ltd Method for reconditioning a hot gas path part of a gas turbine
US9926785B2 (en) * 2013-03-19 2018-03-27 Ansaldo Energia Ip Uk Limited Method for reconditioning a hot gas path part of a gas turbine
US20140315029A1 (en) * 2013-04-17 2014-10-23 General Electric Company Repair process and a repaired component
US9895716B2 (en) * 2013-04-17 2018-02-20 General Electric Company Repair process and a repaired component
CN104110276A (en) * 2013-04-17 2014-10-22 通用电气公司 A repair process and a repaired component
CN106216937A (en) * 2016-08-16 2016-12-14 贵州安吉航空精密铸造有限责任公司 Repairing method for inside metallurgical defects of ZL114A aluminum alloy casting
CN106216936A (en) * 2016-08-16 2016-12-14 贵州安吉航空精密铸造有限责任公司 Repair method of magnesium alloy casting

Similar Documents

Publication Publication Date Title
Feuerstein et al. Technical and economical aspects of current thermal barrier coating systems for gas turbine engines by thermal spray and EBPVD: a review
US5952110A (en) Abrasive ceramic matrix turbine blade tip and method for forming
US6074706A (en) Adhesion of a ceramic layer deposited on an article by casting features in the article surface
US4916022A (en) Titania doped ceramic thermal barrier coatings
US4936745A (en) Thin abradable ceramic air seal
US6451454B1 (en) Turbine engine component having wear coating and method for coating a turbine engine component
US6255001B1 (en) Bond coat for a thermal barrier coating system and method therefor
US5806751A (en) Method of repairing metallic alloy articles, such as gas turbine engine components
US5891267A (en) Thermal barrier coating system and method therefor
US20050235493A1 (en) In-frame repair of gas turbine components
US20020066770A1 (en) Cold spray repair process
US5015502A (en) Ceramic thermal barrier coating with alumina interlayer
US6095755A (en) Gas turbine engine airfoils having increased fatigue strength
US4921405A (en) Dual structure turbine blade
US6355086B2 (en) Method and apparatus for making components by direct laser processing
US6233822B1 (en) Repair of high pressure turbine shrouds
US20040124231A1 (en) Method for coating a substrate
US5866271A (en) Method for bonding thermal barrier coatings to superalloy substrates
EP1398394A1 (en) Cold spraying method for MCrAIX coating
US6444259B1 (en) Thermal barrier coating applied with cold spray technique
US6165628A (en) Protective coatings for metal-based substrates and related processes
US6933061B2 (en) Thermal barrier coating protected by thermally glazed layer and method for preparing same
US5743013A (en) Zirconia-based tipped blades having macrocracked structure and process for producing it
EP0808913A1 (en) Method for repairing a thermal barrier coating
US6575349B2 (en) Method of applying braze materials to a substrate

Legal Events

Date Code Title Description
AS Assignment

Owner name: GENERAL ELECTRIC COMPANY, NEW YORK

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:WHITE, RAYMOND ALAN;LAU, YUK-CHIU;REEL/FRAME:008306/0424

Effective date: 19961111

FPAY Fee payment

Year of fee payment: 4

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
FP Expired due to failure to pay maintenance fee

Effective date: 20060331